They argue solar thermal (also called concentrating solar power, or CSP) is getting cheaper fast, too, because of new, more efficient technologies.

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Previous clean energy investments by Google include eSolar Inc, which builds Concentrating Solar Power (CSP) plants, as well as AltaRock Energy and Potter Drilling, which use various techniques to optimize and develop geothermal energy sources.

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Utility-scale concentrating solar power (CSP) systems that produce electricity using lenses or mirrors to focus radiation on thermal collectors or photovoltaic cells draw criticism from environmental groups for taking up too much desert land, thus displacing certain animal and reptile species.

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